Strange Duncan Behavior

[cambo123]

I have a non-branching duncan coral that has grown from 3 heads to about 15 heads over 8 months. It's in a sumpless 20L under a reefbreeders value LED tuned to less than %25 output. A tunze skimmer and powerhead is used for circulation/filtration. The tank is stocked with several corals, two clowns, a skunk cleaner, and hermits/snails. I keep a close eye on this tank, parameters are held in place with biweekly 20% water changes, feeding is done every 2 to 3 days, and evaporation is covered with an ATO feeding from a RODI (0 TDS) tank. Anyway, this coral does this thing occasionally (once or twice a month) where it will unexpectedly close up and stay closed for 2 to 4 days. Its completely random and happens so fast that on several occasions I have left my room for several minutes only to find when I return the duncan completely closed up. On one occasion I witnessed half the polyps shoot in like a scared feather duster even though they were untouched by anything in the tank. Every time this happens all other corals show no signs of stress. It happened again yesterday and I am curious if this is common behavior.

Thanks

Cameron

 

[organism]

As long as the coral isn't looking stressed it doesn't sound bad, they do weird things sometimes. Is there anything in the tank that might be picking on it? Are you seeing new polyps after it's closed up for a few days?

 

[cambo123]

The skunk cleaner is a suspect. His hideout is in a cave directly underneath the duncan however I have never seen him directly jab at the coral before. I have never noticed new growth however I haven't really checked before. As usual, the coral has slowly come out again.

 

[hoju74]

As long as the coral isn't looking stressed it doesn't sound bad, they do weird things sometimes. Is there anything in the tank that might be picking on it? Are you seeing new polyps after it's closed up for a few days?

Mine always closes up for a day or two when new heads are sprouting too.

 

[bellis31]

Everything sounds fine so far, I would guess it's growing. Mine closes for a period of time also when there are many new heads sprouting.

 

[cambo123]

Interesting, thanks for the input everyone

 

[gbose]

I wouldn't worry about your duncans sulking for a couple of days -- they do that, and are fine again. As I speak, one of mine is closed up like yours....

GBose